SF 995 

^ THE DEVELOPMENT, MORPHOLOGY, 

Copy 1 Af^D ECONOMIC IMPORTANCE 

OF CHICKEN CESTODES 

Morphology of Adult and Larval Cestodes from Poultry 

Studies on the Transmission and Prevention of Cestode 
Infection in Chickens 



BY 



JOHN EARL GUTBERLET 

A. B. Bethany College, Kansas, 1909 
A.M. University of Illinois, 1911 



THESIS 



Submitted in Partial Fulfillment of the Requirements for the 

Degree of 
DOCTOR OF PHILOSOPHY 

IN 

THE GRADUATE SCHOOL 

OF THE 

UNIVERSITY OF ILLINOIS 
1914 



ON THE DEVELOPMENT, MORPHOLOGY, 

AND ECONOMIC IMPORTANCE 

OF CHICKEN CESTODES 

Morphology of Adult and Larval Cestodes from Poultry 

Studies on the Transmission and Prevention of Cestode 
Infection in Chickens 

BY 

JOHN EARL GUTBERLET 

A. B. Bethany College, Kansas, 1909 
A.M. University of Illinois, 1911 



THESIS 



Submitted in Partial Fulfillment of the Requirements for the 

Degree of 
DOCTOR OF PHILOSOPHY 

IN 

THE GRADUATE SCHOOL 
OF THE 

UNIVERSITY OF ILLINOIS 
1914 



Z^XL\Jiny.^f^,AXJ^^'^ I0j3 






m 



MORPHOLOGY OF ADULT AND LARVAL CESTODES 
FROM POULTRY* 

John E. Gutberlet 

During the course of experimental studies on the Hfe history 
of certain chicken cestodes described in the succeeding section of 
this work (Gutberlet, 1916) it was necessary to determine exactly 
the morphological features of the species, which to be sure, had 
been studied by others but were only partially and imperfectly 
known. In the former paper I recorded experiments which demon- 
strated the intermediate stage of Choanotcenia itifundibuliformis to 
be in the common housefly, Musca domestica, and discussed the 
symptoms of infection and methods of control for tapeworm dis- 
eases in chickens. 

In this paper are taken up the structure of the adult and cysti- 
cercus of Choanotcrnia infundibuliformis (Goeze), and also the 
adult form of four other species occuring in chickens of this 
country. 

As described more fully in the preceding paper the worms 
were removed from the intestine under water. The use of normal 
salt solution was avoided since it was found to be injurious. The 
cestodes were killed in a corrosive-acetic solution and preserved in 
70% alcohol and glycerine. Best results were secured by staining 
in Delafield's or Ehrlich's acid hsematoxylin and destaining in acid 
alcohol. 

The five species discussed here were collected at two widely 
separated points, a farm at Hardy, Nebraska, and the poultry farm 
at the University of Illinois. These morphological studies were 
carried on at the Zoological Laboratory of the University of Illi- 
nois. This work was taken up at the suggestion of Dr. Henry B. 
Ward, to whom I am greatly indebted. 



•Contributions from the Zoological Laboratory of the University of Illinois under 
the Direction of Henry B. Ward, No. 57. 



24 john e. gutberlet 

Structure of Adult and Larva (Cysticercus) 

A. ADULT 

ChoanotcBnia infundibtilifonnis (Goeze 1782) Railliet 1896 

1. Diagnosis: Length 50 to 200 mm. Scolex (Fig. 2) small, 
rounded, or conoidal, about 0.4 mm. wide. Rostellum (Fig. 2. 3, r) 
60 to 70/jL in diameter, armed with a single row of 16 to 20 hooks 
(Fig. 8) 25 to 30fi long, with long dorsal root and short ventral 
root. Suckers prominent, elongated antero-posteriorly, length 180 
to 210fi; breadth 135 to 175;u, between the extreme outer edges. 
Neck short and unsegmented. somewhat narrower than broad. In 
specimens well extended neck much narrower than head. Anterior 
proglottids very short and as they become older funnel-shaped, 
much narrower at anterior than at posterior margins; posterior 
segments 1.5 to 2.5 mm. broad and 1.5 to 3 mm. long according to 
amount of contraction, with convex lateral borders, nearly as wide 
at anterior as at posterior margin. Genital pores irregularly alter- 
nating, situated one in each segment in the anterior third of the 
lateral margin, usually under cover of the backward projecting bor- 
der of the preceding segment. Vas deferens (Fig. 14, z'd) and 
vagina pass between excretory canals and dorsal to nerve trunk. 

Male Reproductive Organs: Testicles (Fig. 14, t) 25 to 40 
or more, 60 in some cases, in posterior half of proglottid, posterior 
and lateral to large yolk gland, within limits of excretory canals. 
Vas deferens passes forward and in anterior third of proglottid 
forms a mass of coils between ovary and excretory vessels from 
which it extends outw^ard as a convoluted tube to base of cirrus 
pouch. Cirrus pouch (Fig. 14, 15, r/>) ovoid in shape, 75 to 95/x 
in long diameter. Portion of vas deferens in cirrus pouch is much 
coiled. Cirrus 50 to 65/li long, armed with spines ; outer surface of 
cirrus pouch forms base of deep genital cloaca. 

Female Reproductive Organs: Vaginal opening in genital 
cloaca posterior to cirrus. Vagina posterior to cirrus pouch, after 
crossing ventral excretory canal dilated to form ovoid seminal 
receptacle, posterior and ventral to vas deferens, extending to well 
developed shell gland, 40 to 50/* in diameter located in front of 
middle of proglottid. Transversely elongated ovary (Fig. 14, a) 



MORPHOLOGY OF CESTODES FROM POULTRY 25 

occupies anterior portion of middle field of proglottid in front of 
shell gland. Large yolk gland posterior to ovary and shell gland, 
irregular in shape, elongated transversely, with convex ventral sur- 
face and concave dorsal surface. Uterus (Fig, 16, u) developed 
as tube between anterior and ventral lobes of ovary. Gravid uterus 
fills up most of proglottid, extending beyond excretory canals on 
each side. Eggs oval (Fig. 7), with very thin membrane next em- 
bryo, followed by thick, smooth membrane 40 by 32/* to 45 by 36/1. 
in diameter, and one or two outer membranes, very thin and wrink- 
led in preserved material. Diameter of outer membrane 65 by 40/x 
to 60 by 45/t ; at each pole of outer membrane a delicate appendage. 
Embryonal hooks IS/x long. Embryo 32 by 22/x in diameter. 

2. Morphology: The scolex of the living worm shows up 
very prominently and can be used as a distinguishing feature. 
When first removed from the intestinal wall the suckers appear 
distinct and the neck is much narrower than the scolex. Soon 
after the removal it often contracts and takes on the appearance of 
a flattened bulb which includes the neck and anterior segments 
(Fig. 1). This feature is characteristic of this species and is a 
factor which alone assists very materially in distinguishing it from 
others that occur in chickens. 

The rostrum or crown of the scolex is somewhat pointed when 
the rostellum is enclosed within its sheath (Fig. 2). The rostellum 
is an ovoid structure with a bulbous expansion at its anterior end. 
It has a length of 140/a and a breadth of 60 to 65/* at its anterior 
end. A crown of 18 hooks is arranged in a single row around the 
bulbular anterior end. The structure of the wall is of a fibrous 
nature and presents a transversely striated appearance due to con- 
traction. In the interior of the rostellum the structure is a con- 
nective tissue mass with few cells, some of which possess long 
processes. The hooks (Fig. 8) are 30ju in length with a long dorsal 
root and a short ventral root. 

The rostellar sheath or sac (Fig. 3, rs) into which the rostel- 
lum is withdrawn is oval in shape and 230 to 240/x in length by 80 
to 90ix in width at its broadest point. Histologically, the structure 
is that of a fibrous connective tissue type with spherical and spindle- 
shaped cells. The cells coming in contact with the rostellum, as 



26 JOHN E. GUTBERLET 

well as those on the outer edge of the sac, bear long processes. The 
outer layer of the rostellar sac is composed of longitudinal and 
oblique fibers of a muscular nature which probably have for their 
function the movement of the rostellum. 

The four excretory canals, that have extended forward through 
the entire length of the body, unite in the scolex to form a ring 
(Fig. 3, ex), which lies in the tissue of the rostellar sac around the 
body of the rostellum. 

The suckers are prominent. They are oval in shape and in 
preserved specimens measure 180 to 210/x in length and from 135 
to I75fi in extreme breadth. In the center of each sucker there is 
a depression or an acetabulum, 30 to 4Qfi in diameter. The entire 
inner surface of the suckers possesses minute booklets or spines 
(Fig. 4) 1.5 to 2;u long. These booklets not only line the suckers 
but also extend over the entire surface of the scolex (Figs. 3, 5) 
and down onto the neck region; they disappear before reaching 
the first segment. They appear more distinctly on scolices that are 
somewhat contracted than on those that are well extended. These 
booklets can be seen only in sections as they are too small to be 
distinguished readily in whole mounts. 

Musculature: The longitudinal muscle fibers are arranged in 
bundles which are scattered, forming a loose irregular layer. The 
bundles are numerous and nearly of a uniform size. There are no 
transverse muscle fibers present except a few minute oblique fibers 
which connect some of the longitudinal fibers near the ends of the 
proglottids. Some dorso-ventral fibers are present, but they are 
not abundant. 

Nervous System: The longitudinal nerve fibers are arranged 
in fiber tracts which approach the structure of a nerve cord. The 
individual fibers do not form a compact mass, but are more or less 
free in the tract. Nerve cells have no definite arrangement, but 
are situated irregularly along the fiber tract (Fig. 6). The nerve 
cells are somewhat spindle-shaped and quite large, being from 20 
to 25ix long by 6 to 8/^ wide with large nuclei. Transverse nerves 
are composed of individual cells with long processes extending 
transversely from the lateral fiber tracts. The transverse fibers are 
much scattered and have no definite arrangement except that they 



MORPHOLOGY OF CESTODES FROM POULTRY 27 

are more numerous near the ends of the proglottids. Peripheral 
nerve cells are widely and irregularly distributed. They are more 
numerous at the anterior end of the proglottids, especially on the 
portion that is covered by the backward extension of the preceding 
segment. 

Excretory System: The excretory system is fairly well devel- 
oped in this form. The ventral canal (Fig. 14, v ex) is the larger, 
and has a diameter of 28 to 30/x. A transverse canal unites the 
two longitudinal canals in each segment. The dorsal canals (Fig. 
14, d ex) are much smaller, having a diameter of 6 to 8fi and are 
not united by transverse connections. The four longitudinal canals 
extend anteriorly to the scolex where they unite to form a ring 
wdiich lies in the rostellar sheath around the body of the rostellum. 
The vas deferens and vagina pass between the dorsal and ventral 
excretory canals. 

Male Reproductive Organs: The testes vary in number, us- 
ually from 25 to 40, but in a few cases the number is much greater, 
being as high as 55 or 60, The testes are quite large, being from 
40 to 55/x in diameter, and are located in the posterior half of the 
proglottid (Fig. 14, /), posterior and lateral to the )'^olk gland. The 
testes are not arranged in layers, but are grouped in a more or less 
compact mass almost entirely within the limits of the excretory 
canals. The vas deferens (Fig. 14, vd) in the anterior third of 
the proglottid forms a coiled mass at the side of the ovary, from 
whence it passes laterad to the cirrus pouch as a convoluted tube. 
The portion of the vas deferens inside the cirrus pouch is coiled, 
varying in extent in different specimens (Figs. 14, 15). The vas 
deferens passes into the cirrus. There is no seminal vesicle formed 
by the vas deferens in the cirrus pouch nor are there any accumu- 
lations of sperm cells. The cirrus pouch (Fig. 15) is ovoid in 
shape and is from 75 to 90|Li in diameter. The wall is made up of 
layers of fibers which are both circular and oblique, forming a 
basket-like network which incloses the cirrus and a portion of the 
vas deferens. The outer wall of the cirrus pouch forms the inner 
wall of the deep genital cloaca. The cirrus is a compact structure 
from 50 to 65/x long and lined with spines. It is a slightly curved 
structure passing from the cirrus pouch and curving posteriorly 



28 JOHN E. GUTBERLET 

toward the vagina which is directly posterior to it. The cirrus was 
not observed extending from the genital cloaca, but was noted in 
some specimens curving toward the vagina, though not passing into 
it. A few sperm cells were present in the vas deferens, also in the 
vagina and the seminal receptacle. 

Female Reproductive Organs: The large ovary (Fig. 14, o) 
lies in the anterior third of the proglottid and extends transversely 
across the segment. It has a length of 300/x and a breadth of about 
75 or SOfjL at its broadest point. It is irregular in shape, being com- 
posed of a number of lobes. The end which is nearest the genital 
pore is smaller than the other, allowing room for the mass of coils 
of the vas deferens, the vagina, and the seminal receptacle. The 
ovary is concave on the dorsal surface and convex on the ventral. 
On the dorsal surface of the end nearest the genital pore is located 
the seminal receptacle and the vagina. The ova are large and very 
distinctly shown in the ovary (Fig. 16). Posterior to the ovary is 
the large yolk gland (Fig. 14, 16, ;y) which lies about the middle of 
the proglottid. It is irregularly elongate in shape and extends 
transversely across the segment, having a length of from 120 to 
IZOfjL and a breadth of from 35 to 50/t. Immediately in front of and 
dorsal to the yolk gland and posterior to the ovary is the shell gland 
(Fig. 14, sg) which is slightly ovoid in shape, 40 to 50/x in diameter, 
A small duct, the vitelline duct (Fig. 16, v), passes from the yolk 
gland through the shell gland from which it receives a duct. The 
combined ducts after passing through the shell gland unite with the 
oviduct (Fig. 16, ov) which appears as a curved tube leading from 
the ovary. These united tubes or ducts pass anteriad and slightly 
ventrad into the uterus which develops as a blind tube in the region 
of the ventral lobes of the ovary. This blind tube (Fig. 16, u) 
grows in size and extends transversely across the segment. As it 
becomes larger the tube forms pockets which extend anteriorly and 
posteriorly and also dorsally, until it takes up the entire mass of 
the proglottid between the excretory canals. In gravid segments 
it even extends beyond the excretory canals. A small tube or duct, 
which is really the end of the vagina, connects the seminal recep- 
tacle with the yolk-shell gland duct and oviduct. This tube serves 
to carry the sperm to the eggs in the oviduct for fertilization. The 



MORPHOLOGY OF CESTODES FROM POULTRY 29 

seminal receptacle (Fig. 16, sr) is a dilation of the vagina into an 
oval shaped structure which is about 50/x long and from 25 to 30,a 
in breadth at the widest part. From the seminal receptacle the 
vagina passes laterad, lying posterior to the cirrus pouch, and unites 
with the genital cloaca. The genital cloaca has its pore on the 
lateral margin near the anterior end of the proglottid. The pore is 
usually covered by the backward projection of the segment anterior 
to it. The vas deferens and vagina pass between the dorsal and 
ventral excretory canals and dorsal to the nerve tract. The vas 
deferens is dorsal and anterior to the vagina. 

In the mature segments the uterus becomes filled with ova and 
it increases in size until it occupies the entire area between the 
excretory canals, even extending beyond the canals in the gravid 
proglottids. The uterus finally breaks up into compartments, each 
containing a single embryo. The embryos (Fig. 7) are about 32 
by 22/i, in diameter with onchospheric hooks 18/i. long. Usually 
three membranes, but often four, enclose the embryo. The inner 
membrane is thin and closely surrounds the embryo; the next is 
heavy, being from 1.5 to 2/* thick, composed of fibrous layers with 
a few cells present. This layer is variable in thickness, depending 
considerably upon the amount of contraction of the segment, as it 
ranges in size from 40 to 32/x to 50 by 36ix, or it may be even 
slightly larger. Usually one (Fig. 7) and sometimes two thin mem- 
branes are found on the outside of the thick layer. These are 
often wrinkled and bear at each end an appendage formed from 
the outer membrane by which it is attached to the wall of the cap- 
sule or compartment of the uterus. 

In this species the oldest proglottids drop off from the worm 
before they are fully mature. The embryos from the oldest seg- 
ments on the worm do not show the characteristics of entirely ma- 
ture ones, and there are distinct differences between them and those 
that have been separated from the worm for some time. Single 
proglottids that have separated from the worm are quite active and 
remain in the intestine for some time before passing out with the 
feces. Proof of this is furnished by the fact that a large number 
of the free proglottids are found in the intestine at any time. Even 
tho only a few worms are present in the intestine of a bird there is 



30 JOHN E. GUTBERLET 

usually a large number of free proglottids. If they did not remain 
in the intestine for a considerable length of time there would not 
be nearly as many. Further proof is furnished by the fact that the 
free proglottids have embryos which are mature, showing the oncho- 
spheric characteristics, while the oldest segments that are still at- 
tached to the worm have embryos that are not entirely mature. 
This same condition has been observed in Davainea proglottina as 
Blanchard (1891:435) states that the oldest proglottids separate 
from the others and remain in the intestine to become mature be- 
fore passing out. The proglottids do not always separate from the 
worm singly, but may drop off in groups of three or four. 

The fact that the proglottids separate from the worm before 
they are entirely mature is one of great importance in taking up 
experimental work for infection of intermediate hosts. If the em- 
bryos are fed to insects or other invertebrates before they are ma- 
ture they will be digested, and thus infection cannot be produced. 

B. CYSTICERCUS 

The cysticercus of Choanotcunia infimdibuliformis was found 
in the abdominal region of the body cavity in the common house 
fly, Miisca domestica. The flies had been fed on embryos from 
ripe proglottids of this species of worm, and at the end of twelve 
days were killed. The cysticerci appear to be nearly ripe or ready 
for transmission into the adult host. The time for the develop- 
ment of the cysticercoid varies with different species and under 
different conditions. Grassi and Rovelli (1892:85) found that 
Davainea proglottina developed from the onchosphere into a ripe 
cysticercus in less than twenty days. Schmidt (1894: 9) found that 
the development of the cysticercoid of Drepanidotccnia anatina 
(Krabbe) varied with the time of the year and the influence of the 
temperature. In the summer the embryo developed in an ostracod, 
Cypris ovata, into ripe cysticercoids in two weeks. 

The cyst proper (Figs. 11, 12, c) containing the scolex is oval 
in shape, 220/x long and 120/i in diameter. 

The bladder (Fig. 12, h) or tail, which is also oval in shape, 
is located against one side of the cyst and is somewhat flattened on 
that side. It is 220 to 230jli long and from 116 to 120^i in breadth. 



MORPHOLOGY OF CESTODES FROM POULTRY 31 

The scolex is 80/x in breadth and 120/t in length ; neck is 40/a in 
diameter and 30 to 35/^ long; suckers are 55 to 60/x in diameter. 
The rostellum is 60/t long and 20/* in breadth, armed with a crown 
of 18 hooks arranged in a single row. These hooks (Fig. 9) are 
SOfi long with a long dorsal root and a short ventral root. The 
suckers are lined with numerous minute booklets or spines 1.5 to 2/x 
long which extend over the edges of the suckers and also over the 
greater part of the surface of the scolex, including a part of the 
neck region. Schmidt (1894: 16) described cuticular booklets on 
the suckers of Drepanidotccnia anatina. 

The size of the scolex may be somewhat variable as shown by 
those in the cysticercoids of Drepanidotccnia anatina by Schmidt 
(1894: 10). In that species the intermediate host could be one of 
two or more species of crustaceans and the size of the cysticercoid 
varied with the size of the host in which it was parasitic. 

The head of the rostellum is conical in shape, bearing a bluntly 
pointed apex anterior to the end of the dorsal roots of the hooks 
(Fig. 10, r). This part of the rostellum is composed of minute 
muscle fibers which are both circular and oblique. The rostellum is 
slightly broader below the circle of hooks as it is an oval shaped 
body. 

The rostellar sac (Fig. 10, rs) is a deeply stained structure 10 
to 12jLi thick. It extends from lO/x below the hindermost part of 
the rostellum to the anterior extremity of the scolex, forming an 
oval shaped sac or sheath. It is composed of parenchymatous 
tissue with large heavily stained oval or spindle shaped cells which 
bear processes. The outer part of the sac is composed of a thin 
layer of fine fibers which help to give it a definite shape. At the 
lower edges of the sac the fibers are connected or associated to 
some extent with similar fibers that form the inner layer of the 
suckers. The anterior region of the rostellar sac, which forms 
the sheath for the free head portions of the rostellum, is constructed 
of an inner layer of fine fibers and an outer layer of large spindle- 
shaped cells, the most of which bear fibrous processes at one or 
both ends. 

The suckers are composed of large spindle-shaped cells which 
are arranged perpendicular to the o^dgo:. These are heavily stained 



32 JOHN E. GUTBERLET 

and form a compact layer. The inner boundary of the suckers 
is composed of a layer of fibers which are both circular and oblique. 
Some of these at the upper edges are associated with similar fibers 
in connection with the rostellar sac. 

The cyst is composed of two cell layers with an irregular 
cavity between them. The cells are large and irregular in shape 
with no special arrangement in the layer. Large intercellular 
spaces lie between the cells, thus forming a loose network structure, 
except at the base of the neck. At this point where the neck is 
attached to the inner layer of the cyst the cells are smaller and 
are in a compact mass. There is no definite boundary to the outer 
part of the inner layer as well as to the inner part of the outer 
layer of the cyst. Few cells with long connective processes extend 
across the cavity from one layer to the other. This then forms 
an irregular cavity (Fig. 11 ca) 2 to 20/x in width between the two 
layers of the cyst. This is the primitive cavity of Grassi and 
Rovelli (1889: 373). The two layers of the cyst are formed 
apparently by a fold which extends upward and inward from the 
base of the neck, forming the gastrula cavity of Grassi and Rovelli 
(1889: 402, g) and enclosing the scolex. This cavity varies in 
width from 3 to 10 or 15/*. 

The bladder, an oval shaped structure, is located at one side 
of the cyst and is attached to it at the posterior end by a narrow 
connection (Fig. 12, en). The posterior end of the cyst or the 
region caudad of the base of the neck is somewhat drawn out 
(Fig. 12). From this point is given oflf the attachment to the 
bladder or tail portion of the cysticercoid. The fact that this 
bladder is really a tail, even though it possesses a cavity, is shown 
by the presence of the onchospheric hooks, which are located at 
the end of the bladder opposite to that of the attachment of the 
cyst (Fig. 12, oh). 

The order of arrangement of the onchospheric hooks is indi- 
vidual. In some specimens they are situated at the end of the 
bladder, while in others they are at the side. In some the arrange- 
ment is in a group, vvhile in others they are in pairs. Some of 
my specimens show a pair of embryonic hooks in the layers of 



MORPHOLOGY OF CESTODES FROM POULTRY 



33 



the cyst between the base of the neck and the attachment of the 
bladder, while the other two pairs of hooks are located in the 
bladder. 

The cavity of the bladder is formed apparently by a splitting 
or hollowing out of the cells of the tail, because the wall is con- 
tinuous and of the same histological structure. The wall of the 
bladder is constructed of two layers, an inner cell layer and an 
outer cuticular layer. The outer cuticular layer is more or less 
striated on account of minute fibrils uniting it with the inner cell 
layer. Histologically, the structure of the inner layer is con- 
structed of somewhat granular substance arranged in fibers form- 
ing a network which encloses clear spherical cells with large nuclei 
(Fig. 13). Outside of the cuticular layer is located the peritoneum 
of the host which lies upon the bladder and surrounds it as well 
as the cyst. 

C. COMPARISON OF ADULT AND CYSTICERCUS 

A comparative study of the adult and the cysticercoid shows 
the likeness which exists between them. The presence of the 
same number of hooks, having exactly the same size and shape 
as seen by comparing Figures 8 and 9. Minute booklets of the 
same size are present in both cysticercoid and adult lining the suck- 
ers, the entire surface of the scolex and a part of the neck region. 
Rosseter (1891: 365) shows that the hooks on the rostellum and 
suckers of Echinocotylus Rosscteri undergo no changes during 
the act of transition from cysticercus to adult stage. The rpstellar 
sac is of the same general shape in both. The head of the rostel- 
lum is not expanded in the cysticercoid as in the adult because it 
has not functioned as yet. This corresponds to figures as shov/n 
by Schmidt (1894, PI. VI, Fig. A) of the cysticercoid and Krabbe 
(1869, PI. VI, Fig. 114) of the adult of Drepanidotania anatina, 
and by Grassi and Rovelli (1892, PI. IV, Fig. 7, 8) of the cysti- 
cercoid and Blanchard (1891: 16) of the scolex of Davainca 
proglottina. No measurements are given for the rostellum of 
either the cysticercoid or the adult by the above authors. 

There is a great deal of difiFerence in the size of the scolex 
between the cysticercoid and the adult. In my specimens the 



34 JOHN E. GUTBERLET 

scolex of the adult is between four and five times as large as that 
of the cysticercoid. The scolex of the cysticercoid has as yet 
not functioned so that the musculature of the organs is not devel- 
oped as in the adult, consequently is not nearly as massive. The 
cells also are smaller than those of the adult. 

Schmidt (1894: 10, 44) shows that the adult scolex of Dre- 
panidota;nia anatina is about three times as large as that of the 
cysticercoid. He also states that the size of the cysticercoid may 
vary with the size of its host. 

Different forms become modified in changing from the inter- 
mediate to the adult hosts as shown by Schmidt (1894) in Dre- 
panidotcenia anatina, Rosseter (1891) in Echinocotylus Rosseteri, 
and Grassi and Rovelli (1892) in Davainea proglottina. 

Onchospheric hooks in the wall of the tail are the same size 
(18ju,) and shape as those of the embryos found in the mature 
proglottids. 

A consideration of these factors of morphological significance 
which demonstrate the resemblances between the cysticercoid and 
adult, indicates clearly that this cysticercoid is the intermediate 
stage of Choanotcenia infundihidifor^nis. 

OTHER CHICKEN CESTODES IN THE UNITED STATES 

1. Davainea tetragona (Molin 1858) Blanchard 1891 
Diagnosis: Length 10 to 250 mm. by 1 to 2.5 mm. in breadth, 
varying with state of contraction. Scolex (Fig. 19) 175 to 215jLt 
in diameter, with retractile rostellum 25 to 50/a in diameter, armed 
with single row of about 100 hooks. Rostellar hooks (Fig. 20) 
6 to 9^ long through longest axis, hammer-shaped, with long ven- 
tral root and short dorsal root, prong short and recurved. Suckers 
oval, 60 to llOyu. in diameter, armed with 8 to 10 rows of small 
hooks of various sizes. Acetabular hooks (Fig. 21) range in 
size from 4 to 8/x, through longest axis, having thorn-like 
prong, short dorsal root, and longer flattened ventral root, which 
is shorter than prong. Neck long and slender, but often as broad 
as head. Segments trapezoidal and imbricate, edges of strobila 
serrate. Oldest segments usually longer than broad, often bell- 



MORPHOLOGY OF CESTODES FROM POULTRY 35 

shaped. Genital pores usually unilateral, situated one in each 
segment, at or in front of middle of lateral margin, frequently 
marked off by papilla. Male and female canals pass on dorsal 
side of nerve and excretory vessels, 

Male Reproductive Organs: Testes 20 to 30 in median field 
surrounding female organs, most of them lying on aporose side 
of latter. Vas deferens situated in anterior third of segment, 
beginning near median line, and extending in much convoluted 
course laterally to base of cirrus pouch which it enters and, after 
a few coils in basal portion of latter, passes into cirrus. Cirrus 
pouch pyriform, 75 to 100/x in length. Basal portion surrounded 
by prominent layer of longitudinal muscle fibers, neck with thick 
layer of transverse fibers. Cirrus without apparent spines. 

Female Reproductive Organs: Ovary in middle of segment. 
Yolk gland posterior to ovary, irregularly reniform, slightly longer 
in its transverse axis, about 100/j. in diameter. Shell gland promi- 
nent, 50yx in diameter, immediately in front of yolk gland. Vagina 
begins at genital pore, posterior to opening of cirrus pouch, at 
first very slender but at distance of 15 to 25 fi from genital pore 
swells out into thick-walled tube, functioning as seminal recep- 
tacle. This extends transversely across segment and joins oviduct 
on dorsal side of ovary near median line. Oviduct, after being 
joined in shell gland by vitelline duct, proceeds forward and ends 
on dorsal side of ovary. Definite and persistent uterus not devel- 
oped. Eggs pass from distal end of oviduct, become imbedded 
in fibrous and granular or gelatinous mass which fills up most of 
segment. This mass divides into 50 to 100 portions to form egg 
capsules, each surrounded by membrane and containing 6 to 12 
or more eggs. Egg is surrounded by three envelopes, — inner, close 
to onchosphere, often scarcely visible; middle layer or envelope 
much folded, giving appearance of network between inner and 
outer membranes ; and smooth outer envelope. The onchosphere 
measures 10 to IS/x in diameter; the outer envelope measures from 
25 to 50;Lt in diameter. 



One point noted here that has not been mentioned before by 
other authors is that the genital pores are irregularly alternate. 



36 JOHN E. GUTBERLET 

They are usually unilateral. The existence of this irregularly 
alternate occurrence of the genital pores may be an anomaly, but 
it is rather frequent for such a condition. 

2. Davainea echinobothrida (Megnin 1880) Blanchard 1891 

Diagnosis: Length up to 250mm; width 1 to 4 mm. Head 
(Fig. 22) 0.25 to 0.45 mm. in diameter, with retractile rostellum 
100 to I50fi in diameter, armed with crown of about 200 hooks 
arranged in two rows. Suckers round or oval, 90 to 200/a in diam- 
eter, armed with 8 to 10 rows of hooks. Rostellar hooks (Fig. 
23) similar to those of Davainea tetragona, but larger, measuring 
10 to 13/x in length. Acetabular hooks (Fig. 24) likewise similar 
to those of D. tetragona, but also larger; size variable, smallest 
being 7 or 8/u, in length and largest measuring from 14 to 16/x. 
Neck thicker and generally shorter than D. tetragona, nearly equal 
to width of head. Strobila resembling that of D. tetragona, but 
serrate border more pronounced. Oldest segments in preserved 
specimens also differ from those of D. tetragona, being less elon- 
gate and frequently marked by median constriction. Owing to 
this constriction adjacent borders of most posterior segments pull 
apart in median line and remain joined only at sides, giving rise 
to median series of openings through posterior portion of strobila. 
Genital pores irregularly alternate, or sometimes almost entirely 
unilateral, situated one in each segment posterior- to middle of 
lateral margin. Male and female canals pass on dorsal side of 
nerve and excretory vessels. 

Male Reprodnctix'e Organs: Testes 20 to 30, arranged in 
median field surrounding female glands as in D. tetragona. Vas 
deferens lies in anterior third of segment much as in D. tetragona. 
Cirrus pouch flask-shaped, 130 to 180/i, in length. Basal portion 
globular or ovoid, surrounded by layer, about 10/x thick, of longi- 
tudinal muscle fibers inside of which is a layer about 12/i thick 
of transverse fibers. Neck of pouch measures 50/x to JSfx in length 
by 15 to 20/x in diameter, surrounded by layer of transverse fibers 
thickened at distal end to form sphincter. According to Megnin, 
the cirrus is armed with minute spines. 

Female Reproductiz'e Organs: Female organs same as in 
Davainea tetragona, and onchospheres (Fig. 25) are also similar 



MORPHOLOGY OF CESTODES FROM POULTRY 37 

in structure and size, 14 to IS/a in diameter. Onchospheric hooks 
6 to 7/Ji long. Egg capsules in groups of 6 to 12 or more, em- 
bedded in a fibrous gelatinous mass. 

In the living specimens very little difiference can be noticed 
except in size of the species D. tetragona and D. echinohothrida. 
They are both quite transparent and appear much alike in every 
respect in external appearance, except that D. tetragona is slightly 
more transparent, while the oldest segments of D. echinobothrida 
have very distinct median constrictions between them, appearing 
almost as a series of openings. 

The chief diiTerences between D. tetragona and D. echinohoth- 
rida are that in the latter the animal is larger, the hooks are more 
numerous and larger, and the structure and size of the cirrus 
pouches show a very distinct difiference. There is also a difference 
in the pathological effect of these spiny-suckered forms. D. echino- 
bothrida produces large nodules or ulcers in the intestinal 
wall. The scolex bores through the mucosa of the intestine and 
in some cases nearly through the muscular coats. This disease 
in fowls is termed "nodular tseniasis", as described by Moore 
(1895: 1), and is often mistaken for other diseases. 

3. Davainea cesticiUiis (Molin 1858) Blanchard 1891 
Diagnosis: Length 10 to 125 mm. Maximum width 1.5 to 
3 mm. Head cyhndrical (Fig. 28), sometimes spheriodal, 0.3 to 
0.6 mm. wide and 0.2 to 0.4 mm. long. Suckers unarmed, about 
100/i, in diameter. Rostellum broad and flat or hemispherical, 0.25 
to 0.35 mm. wide, armed with a crown of 200 to 300 hooks which 
are very unstable and easily lost, arranged in two ranks. Hooks 
(Fig. 29) 8 to l2fjL long with short dorsal root and long ventral 
root. Neck very short. Anterior segments three to five times 
as broad as long; the following increase in size until they become 
equal in length and breadth and finally even longer than broad ; 
borders overlapping. Genital pores irregularly alternate, one in 
each segment, somewhat in front of middle of lateral margin in 
young segments and nearer the middle in older segments. Vagina 
and cirrus pouch pass dorsal of the two excretory canals and 
nerve. 



38 JOHN E. GUTBERLET 

Male Reproductive Organs: Testes (Fig. 17, /) 20 to 30 in 
number in posterior portion of segment. Vas deferens much 
coiled before entering base of cirrus pouch, also coiled within latter. 
Cirrus pouch ellipsoidal, 120 to 150,u long by 55 to 70fi wide. 
Cirrus when protracted 10/x in diameter, armed with minute spines, 
and with bulbous enlargement 20/a in diameter at its base, where 
it becomes continuous with cirrus pouch. 

Female Reproductive Organs: Vagina enlarged before reach- 
ing median line into small seminal receptacle (Fig. 17, sr). Ovary 
occupies middle field in front of testes. Yolk gland and shell 
gland posterior to ovary, ventral and dorsal, respectively, in rela- 
tive position. Uterus at first in front of ovary as cord of cells ; 
gradually increasing in size, finally occupies most of segment and 
frequently extends laterally beyond excretory canals. In oldest 
proglottids it becomes divided into compartments, or capsules, 
each containing a single egg. Embryo (Fig. 30) 36 by 27 ix in 
diameter, with very thin membrane closely adherent to surface. 
Embryo further enveloped by thicker, smooth fibrous membrane, 
oval in shape, 45 to 40ju, in diameter, with filament at each pole 
attaching to thin outer wrinkled membrane about 35 by 50/x in diam- 
eter: finally egg is surrounded by capsule composed of outer and 
inner membrane, latter closely adherent to or fused with outer 
egg membrane; and former more or less widely separated from 
latter and connected with it by number of septa. 



One of the principal points noted here that is not mentioned 
by other authors is the size of the rostellar hooks. In my speci- 
mens they seem to be somewhat larger than those described by 
others. They have been described as being 8 to lOju, long, while 
my forms show many of them to be distinctly 12/i. in length. A 
second point noted here is the method of the development of the 
uterus. The uterus develops in front of the ovary. It first ap- 
pears as a solid cord of cells connected with the united ducts of 
the ovary, shell gland, and yolk gland. The solid cord of cells 
which later gives rise to the uterus becomes hollow and appears 
as a blind sac or tube. This then grows in size, forming pockets, 
and finally fills up the entire proglottid. 



MORPHOLOGY OF CESTODES FROM POULTRY 39 

This form is one of the most common chicken tapeworms 
and is the most easily recognized. It can be identified by the head 
with its broad, flat rostellum which shows up very prominently; 
the width of the most anterior segments is usually equal to or 
greater than the width of the head, and the eggs are distributed 
in individual egg capsules in mature proglottids. 

4. Hymenolepis carioca (Magalhaes 1898) Ransom 1902 
Diagnosis: Length 30 to 80 mm. Breadth at neck 75 to 150/u,, 
at posterior end 0.5 to 0.7 mm. Segments three to five times or 
more broader than long throughout strobila. Head (Fig. 26) 
flattened dorso-ventrally, 140 to 160/t long, 150 to 215/a wide and 
100 to 140/i. thick. Suckers shallow, 70 to 90/x in diameter, un- 
armed. Rostellum unarmed ; in retracted position 25 to 40/i in 
diameter and 90 to 100/* in length, with small pocket opening to 
exterior in anterior position. Unsegmented neck portion of strobila 
0.6 to 1.5 mm. long. Genital pores almost entirely unilateral, a 
single pore being located in each segment slightly in front of middle 
of right-hand margin. 

Male Reproductive Organs: Testicles three in number, nor- 
mally two on left and one on right of median line. On dorsal 
side of inner end of cirrus pouch vas deferens is swollen into 
prominent seminal vesicle (Fig. 18, sz') which may attain a size 
of 70 by SO/JL. Cirrus pouch (Fig. 18, cp) in sexually mature 
segments 120 to 175/x long by 15 to 18/x in diameter; almost cylindri- 
cal, slightly curved toward ventral surface of segment; on outer 
surface about 20 longitudinal muscle bands, 2 to 3/* in thickness, 
very prominent in cross section; vas deferens enlarged within 
cirrus pouch to form small seminal reservoir occupying proximal 
two-thirds of pouch; distal third of portion of vas deferens within 
pouch very slender, about 1/x in diameter and functions as cirrus. 
Genital cloaca 12 to 36/i. deep. 

Female Reproductive Organs: Opening of vagina in floor of 
genital cloaca, ventral and posterior to cirrus opening. First por- 
tion of vagina very narrow, 1/* in diameter. Small vaginal sphinc- 
ter 8 to lO/i from vaginal opening. On inner side of sphincter 
vagina gradually increases in diameter, and in sexually mature 



40 JOHN E. GUTBERLET 

segments swollen into prominent seminal receptacle (Fig. 18, sr} 
which extends forward to anterior border of segment and inward 
considerable distance beyond proximal end of cirrus pouch. Ovary 
faintly bilobed or trilobed in posterior half of proglottid. Yolk 
gland spherical or ovoid, 30 to 40/x in diameter, situated near median 
line of segment, posterior and dorsal of ovary. Uterus at first 
solid cord of cells extending transversely across segment along 
anterior border of ovary; becomes hollowed out and grows back- 
ward on dorsal side of ovary; in gravid segments occupies nearly 
entire segment and filled with eggs. Eggs (Fig. 27) in gravid 
uterus spherical or oval, with four thin membranes, the two middle 
membranes often approximate to form thick layer which shows 
somewhat of a cellular or coarse granular structure. Diameter of 
outer membrane 36 by 36fi to 75 by 70/*, of outer middle mem- 
brane 30 by 30/i, to 65 by 60/ji, of inner middle membrane 26 by 
26fi to 40 by 35/x, of inner membrane 24 by 16/x to 29 by 21/i,. This 
membrane often lies so close to onchosphere that it can scarcely 
be distinguished from edge of embryo. Onchosphere is 18 by 14 
to 27 by l9fjL in diameter; length of embryonal hooks 10 to I2ix. 
This form is thread-like and usually occurs in great numbers. 
It is very delicate and fragile and can be recognized by that fact 
alone, as it is the most fragile of the chicken forms known. 

SUMMARY 

1. By morphological comparison of the cysticercoids produced 
experimentally in flies and adult of Choayiatcenia infiindibuliformis 
they are shown to be identical. 

2. Morphological points noted are the presence of minute 
booklets on the suckers and entire surface of scolex in Choanatcenia 
infundibuliformis. The manner of development of uterus in the 
same species is by means of a blind tube which grows in size, 
forming pockets, and later breaks up into small compartments. 
In Davainea tetragona the genital pores were found to occur irreg- 
ularly alternate in the proglottids. The hooks on the rostellum 
of Davainea cesticillus were found to vary in length from 8 to 
12/u,. The uterus in development first appears as a solid cord of 
cells which becomes hollow and in growing forms pockets, filling 
the entire proglottid. 



MORPHOLOGY OF CESTODES FROM POULTRY 41 

BIBLIOGRAPHY 
Blanchard, R. 

1891. Notices helminthologiques. Sur les teniades a ventouses armees. 
Mem. soc. zool. France., 4: 420-489. 

Davaine, C. 

1877. Traite des entozoaires et des maladies vermineuses de I'homme et 
des animaux domestiques. Paris. Ed. 2, 1003 p. 

Grassi, B., and Roveixi, G. 

1888. Bandwiirmer Entwickelung. I. Centralbl. Bakt. und Parasitenk., 
3: 173. 

1889. Embryologische Forschungen an Cestoden. Centralbl. Bakt. und 
Parasitenk., 5: 2>7f)-2,77 ; 401-410. 

1892. Ricerche embriologiche sui Cestodi. Atti. Accad. Gioenia Sci. 
Nat. in Catania, 4: 1-108. 

GUTBERLET, J. E. 

1916. Studies on the Transmission and Prevention of Cestode Infection 

in Chickens. (In Press.) 
Hassall, a. 

1896. Bibliography of Tapeworms of Poultry. Bull. Bur. An. Ind., 12: 

81-88. 

Krabbe, H. 

1869. Bidrag til Kundskat om Fuglenes Baendelorme. Vid Selsk. Skr. 
V. Roekke. Nat. og Math., 8: 251-368. 

Magalhaes, p. S. de 

1898. Notes d'helminthologie Bresilienne. Arch. Parasit., 1 : 442-451. 

MOLIN, R. 

1858. Prospectus helminthum, quae in prodromo faunae helminthologicas 
Venetiae continentur. Sitzber. k. Akad. Wiss. Wien, math, naturw. 
kl., 30: 127-158. 

Moore, V. A. 

1895. A Nodular Taeniasis in Fowls. Bur. An. Ind. Cir. 3; 4 pp. 

Mrazek, Al. 

1907. Cestoden Studien. I. Cysticercoidcn aus Lumbriculus variegatus. 
Zool. Jahrb., Syst., 24: 591-624. 

Piana, G. p. 

1882. Di una nuova specie di Tenia del gallo domestico (Taenie bothri- 
oplitis) e di un nuova cisticerco delle lumachelle terrestri (Cysti- 
cercus bothrioplitis). Mem. Accad. Sci. Inst. Bologna, 2: 387-394. 



42 JOHN E. GUTBERLET 

Ransom, B. H. 

1900. A new Avian Cestode-Metroliasthes lucida. Trans. Amer. Micr. 

Soc, 21 : 213-226. 
1902. On Hymenolepis carioca (Magalhaes) and H. megalope (Nitzsch) 

with Remarks on the Classification of the Group. Trans. Amer. 

Micr. Soc, 23 : 151-172. 
1904. The Tapeworms of American Chickens and Turkeys. Ann. Report 

Bur. An. Ind., 21 : 268-285. 
1904a. Hanson's Eye-worm of Chickens (Oxyspirura Mansoni). Spiny- 

Suckered Tapeworms of Chickens. Bull. Bur. An. Ind., 60 ; 72 pp. 
1909. The Taenoid Cestodes of North American Birds. Bull. U. S. Nat. 

Mus., 69: 1-141. 
1911. A New Cestode from an African Bustard. Proc. U. S. Nat. Mus., 

40: 637-647. 

ROSSETER, T. B. 

1890. Cysticercoids parasitic in Cypris cinerea. Jour. Micr. Nat. Sci., 9: 
241-247. 

1891. Sur un cysticercoide des Ostracodes, capable de se developper dans 
I'intestin du canard. Bull. soc. zool. France, 16: 224-229. 

1892. On a New Cysticercus and a New Tapeworm. Joum. Queckett 
Micr. Club, 4: 361-366. 

1897. On Experimental Infection of Ducks with Cysticercus coronula 
Mrazek (Rosseter), Cysticercus gracilis (von Linstow), Cysti- 
cercus tenuirostris (Hamann). Joum. Queckett Micr. Club, 6: 
397-405. 

Schmidt, J. E. 

1894. Die Entwicklungsgeschichte und der anatomische Bau der Taenia 
anatina (Krabbe). Arch. Naturg., 1: 65-112. 

Stiles, C. W. 

1896. Report upon the Present Knowledge of the Tapeworms of Poultry. 
Bull. Bur. An. Ind., 12; 78 pp. 

TOWEB, W. L. 

1900. The Nervous System of the Cestode Monezia Expansa. Zool. 
Jahrb. Anat., 13: 359-384. 



MORPHOLOGY OF CESTODES FROM POULTRY 43 

EXPLANATION OF PLATES 

Unless otherwise stated all drawing were made with the aid of a camera 
lucida. 

Abbreviations 

b — bladder rs — rostellar sac 

c — cyst sg — shell gland 

ca — primitive cavity sr — seminal receptacle 

en — connection of bladder with cyst sv — seminal vesicle 

cp — cirrus pouch t — testes 

dex — dorsal excretory canal u — uterus 

ex — excretory ring in scolex v — vitelline duct 

0— ovary z^a— vagina 

oh — onchospheric hooks vd — vas deferens 

Q-u — oviduct vex — ventral excretory canal 

r— rostellum 3»— yolk gland 

Plate V 

CHOANOTAENIA INFUNDIBULIFORMIS 

Fig. 1. Scolex much contracted. x40 

Fig. 2. Scolex normal extension. xl45 

Fig. 3. Longitudinal section of scolex, showing rostellum and rostellar sac. 

x425 

Fig. 4. Section of portion of sucker, showing booklets. x425 

Fig. 5. Section of portion of wall of scolex, showing booklets. x42S 

Fig. 6. Longitudinal nerve tract, showing nerve cells with processes. x6S0 

Plate VI 

Fig. 7. A, B, C, D. Embryos from mature proglottid. x425 
Fig. 8. Hooks from rostellum of adult. x425 

CYSTICERCUS of CHOANOTAENIA INFUNDIBULIFORMIS 

Fig. 9. Hooks from rostellum of cysticercus. x42S 

Fig. 10. Section through scolex, showing rostellum with hooks and rostellar 

sac. x425 
Fig. 11. Section through scolex and cyst, showing suckers with booklets, 

structure of cyst and primitive cavity between layers of cyst. x42S 
Fig. 12. Reconstruction of cysticercus with cyst and bladder or tail, showing 

scolex in cyst and onchospheric books in bladder. xl45 
Fig. 13. Section of wall of bladder, showing histological structure and 

peritoneum of host. x425 



44 JOHN E. GUTBERLET 

Plate VII 

Fig. 14. Choanotaenia infundibuHformis. Reconstruction of mature pro- 
glottid, showing reproductive organs, excretory vessels, and nerve. 
xl4S 

Fig. 15. C. infundibuHformis. Reconstruction of cirrus pouch showing 
cirrus and vas deferens, also part of vagina in connection with 
cloaca. x310 

Fig. 16. C. infundibuHformis. Reconstruction of female reproductive or- 
gans, showing part of ovary, yolk gland, shell gland, oviduct, 
vitelline duct, uterus, and connection of ducts with uterus and 
seminal receptacle. x310 

Fig. 17. Davainea cesticillus. Reconstruction of mature proglottid, showing 
reproductive organs and excretory vessels.^ xl45 

Fig. 18. Hymenolepis carioca. Reconstruction of mature proglottids, show- 
ing reproductive organs from ventral view. xl45 

Plate VIII 

Scolex of Davainea tetragona. xl45 
Hooks from rostellum of D. tetragona. x425 
Hooks from suckers of D. tetragona. x425 
Scolex of Davainea echinobothrida. xl45 
Hooks from rostellum of D. echinobothrida. x42S 
Hooks from suckers of D. echinobothrida. x425 
Embryos of D. echinobothrida, showing capsule and fibrous gel- 
atinous mass in which it is embedded. x425 
Scolex of Hymenolepis carioca, after Ransom. 

A, B, C, D. Embr>os of Hymenolepis carioca, showing enveloping 
membranes. x42S 

Fig. 28. Scolex of Davainea cesticillus. Free-hand drawing of living spec- 
imen well extended, showing rostellum. 

Fig. 29. Hooks from rostellum of D. cesticillus. x42S 

Fig. 30. A, B, C, D. Embryos of D. cesticillus, showing enveloping meni- 
branes. x425 



Fig. 


19. 


Fig. 


20. 


Fig. 


21. 


Fig. 


22. 


Fig. 


23. 


Fig. 


24. 


Fig. 


25. 


Fig. 


26. 


Fig. 


27. 










Plate V 




^- 




B 






Plate VI 




Plate VII 




19 







22 



f r r 



29 



•'«^ 





20 



T A 






21 




^T 



23 






84 




Plate VIII 



Contributions from the Zoological Laboratory of the University of Illinois, 
under the Direction of Henry B. Ward, No. 62. 



STUDIES ON THE TRANSMISSION AND PREVENTION 
OF CESTODE INFECTION IN CHICKENS 



John E. Gutberlet, Carroll College, Waukesha, Wis. 



Introduction. The problem of tapeworm infection in chickens 
has received but little attention in the United States. In fact it 
was entirely untouched until a few years ago when the subject was 
opened by Stiles (1896) and work was begun by Ransom (1900, 
1902, 1904, 1909) on poultry and other birds. At the present time 
less than a dozen references constitutes the entire American lit- 
erature on the subject. Five species of cestodes are known to in- 
fest chickens in various parts of the United States. 

No work has been done on the life history of the forms 
existing in this country. However, studies have been carried 
on extensively with poultry cestodes in various other parts of the 
world, though as yet very little has been finally determined. In 
only one species of chicken cestode has the life cycle been demon- 
strated experimentally. That is Davainea proglottina (Davaine) 
for which Grassi and Rovelli (1889 : 372 ; 1892 : 30, 85) have shown 
that the intermediate host is a slug (Limax cinereus). This species 
of cestode has not as yet been reported in this country. 

Chickens are supposed to become infested with another species 
through eating snails, a third through eating flies, and a fourth 
through eating earthworms. Plana (1881-1882) found in a snail 
(Helix) two cystieercoids which agree closely with the head of 
Davainea tetragotia (Molin). No experiments were performed to 
demonstrate that the cysticercoid was the larval stage of that 
species and the only evidence of their connection is the similarity 
in form. Grassi and Rovelli (1892: 33, 87) found in flies cystieer- 
coids which closely resembled Choanotaenia infiuidihuliformis and 
base their conclusion of identity on the structural similarity. 

Grassi and Rovelli (1889 : 372 ; 1892 : 29) found in earthworms 
(Allolhophora foetida) cystieercoids which they associated w^ith the 
scolex of Dicranotaenia sphenoides, a chicken cestode not reported 
in this country. Here again the only evidence for regarding it to 
be the larval stage of this species is a general structural likeness. 
In no one of these three forms was the life cycle demonstrated ex- 
perimentally. Such comparisons are not proof that the cystieer- 
coids are intermediate stages of definite species, but only give a 
clue as to the probable life cycle. 



CESTODE INFECTION IN CHICKENS 219 

In other kinds of poultry more has been done on the life his- 
tories of their eestodes. The life cycles of five species of duck 
eestodes have been demonstrated through experiment. Schmidt 
(1894) proved that Drepanidotaenia anatina (Krabbe) has its in- 
termediate stage in a fresh-water crustacean (Cypris ovata). He 
fed large quantities of tapeworm eggs to the crustaceans and found 
that the larvae developed in two weeks during the summer. Ros- 
seter (1891, 1892) has shown that a second duck cestode, Echino- 
cotylus Rosseteri (Blanchard), has its intermediate stage in an- 
other small fresh-water crustacean (Cypris cinereus). He fed large 
numbers of the crustaceans to ducks which upon examination later 
yielded a large crop of tapeworms of the species named. 

Rosseter (1897) also demonstrated experimentally the life his- 
tories of three otlier species of duck eestodes. He had discovered 
some cysticerci in crustaceans which he compared with the adult 
\vorms occurring in ducks and found that they agreed closely. He 
produced Dicranotaenia coronula in a duck by feeding it Cypris 
cinerea. Drepanidotaenia gracilis was introduced into the ducks 
through Cypris cinerea and Cypris viriens: Drepanidotaenia 
tenuirostris was likewise raised by feeding Cyclops agilis. 

As in other cases the question of control of infection in chickens 
depends to a great extent upon the life history of the parasites. 
Little can be done to wipe out the disease until more is known of 
its source. Certain methods may be employed to check it, but as 
yet it has been impossible to prove the exact source of infection. 
Usually it is easiest to control such forms during the developmental 
stages. 

This paper is the result of some investigations carried on to 
find out the life history of certain chicken tapeworms. Numerous 
experiments were tried on various insects and many observations 
made on the habits of the birds in the endeavor to ascertain where 
the cause of the infection was located. The habits of the birds are 
probably the chief factors to be dealt with in experiments of this 
kind. Certain insects that are common about the habitats of the 
birds are readily eaten. They are hence more likely to be inter- 
mediate hosts than those which are rare in these localities. Such 
factors have been taken into consideration and through experiment 
it has been shown that one cestode, Choanotaenia infundibuli- 
formis, has its intermediate stage in the common house-fly. 

The most of the material was collected, and the experimental 



220 JOHN E. GUTBERLET 



work was done on a farm at Hardy, Nebraska. A large amount of 
material was also collected at the poultry farm at the University 
of Illinois. 

Thanks are due to Professor D. 0. Barto, of the University 
of Illinois, for giving me the privilege of collecting material at 
the poultry farm. For other assistance I am indebted to my father 
and motlier, William and Flora Gutberlet, for their untiring efforts 
to make this work a success by taking records and making collec- 
tions of material at times of the year when they would not otherwise 
have been taken. 

I wish to express my appreciation to Dr. Henry B. Ward, at 
whose suggestion this work was first taken up, for his helpful sug- 
gestions and criticisms during the preparation of this paper. 

Methods of Technic. In making collections of tapeworms 
the intestine of the bird was slit open under water and the con- 
tents removed by shaking gently. The worms are usually attached 
to the wall and can be easily seen and removed with the aid of a 
pair of needles. Those that are not attached sink to the bottom of 
the dish. 

In removing the worms from the intestine it was found best 
to transfer them directly to fresh water. A weak saline solution 
was demonstrated to be harmful as the worms die in it in a very 
short time. Tower (1900: 362) found saline solution harmful to 
cattle cestodes (Monezia), In fresh water, the worms soon become 
well extended and remain alive and normal for twelve to fifteen 
hours, or even longer. The worms are best killed in a corrosive- 
acetic solution and preserved in 70% alcohol and glycerine. For 
study of structure and accurate diagnosis of species the worms 
were cut in sections from 5 to 10 microns in thickness, stained in 
Delafield's or Ehrlich's acid haematoxylin and . destained in acid 
alcohol. 

In order to use house-flies for experimental purposes one has 
to work out first, methods of keeping them alive. The flies used 
were kept for experiment in small cages. They demanded a great 
deal of attention because the slightest disturbance of conditions 
was harmful. They were fed most satisfactorily on blood, liver, 
and spleen. It was found that a fly could not live long without- 
a constant supply of water in the cages. The cages had also to be 
placed in the sun for a few minutes each morning, and then kept 
in the shade for the rest of the day, but not in a cool place. 



CESTODE INFECTION IN CHICKENS 221 



At the conclusion of the experiment the flies were killed, fixed in 
corrosive-acetic solution and preserved in 70% alcohol. The chitin 
covering of the body of the flies was punctured to allow these 
fluids to penetrate properly. 

Large bottles proved very satisfactory as cages for beetles 
during the experiments. The bottles were fitted with glass or 
metal stoppers provided with pores for the passage of air. Leaves 
and a small amount of soil were placed in the bottom of the bottle. 
The beetles were killed and preserved like the flies, but before 
sectioning the chitin covering was removed by dissection. 

Amount of Infection. The flock of chickens upon which 
these studies were carried on was so heavily infected with the tape- 
worm disease during certain seasons that it was rather unusual to 
find a bird that did not harbor at least a few of the parasites. The 
investigations extended over a period of two summers. Close ob- 
servations were made during those seasons, and also at several 
other times during the year, to secure a record of the amount of 
infection during other seasons than the summer months. 

The first summer (1912) about fifty chickens were examined 
for parasites. Eight of these were adults and in no case was there 
any nifection. Ten young birds from six weeks to two months old 
were examined in June, but none of them were infected. The first in- 
fection of tapeworms for that year was detected on July 25. Between 
that date and September 9, thirty-two young birds were examined 
and every one showed some infection. In some it was slight, while 
in others it was very heavy. During this same period, between 
July 25 and September 9, some adult birds were examined but 
yielded no parasites. 

During the summer of 1913 forty birds were examined between 
August 10 and September 18, with some infection in every bird. 
A few of these were adult birds which had only a few parasites. 
The young birds were more heavily infected, although the number 
of parasites varied with different birds. In one bird which was ex- 
amined at the age of seven weeks, twenty-five tapeworms were 
found. Between June 17 and August 1, eight birds were examined 
and cestodes were present in every bird with the exception of one 
adult killed on June 24. 

I have records of infection in the flock for January 1 and 
April 27, 1913, and for November 20, December 2, and December 
26, 1913. There are five species of worms infesting the chickens 
in this place and further details are given in the table. 



222 JOHN E. GUTBERLET 



Between June 20 and August 1, 1913, examinations were made 
of about fifteen birds at Urbana, 111. Some of these were from 
the poultry farm at the University of Illinois and others were from 
private yards of residents in this vicinity; in only one bird was 
there any trace of an infection. In that case there were a few 
fragments of worms which were in such a state of disintegration 
that they could not be preserved or determined. No further ex- 
aminations for parasites were made in this locality until December 
2, 1913, when it was discovered that the chickens at the poultry 
farm at the University of Illinois were badly infested. Several 
were examined and found to harbor Davainea cchinohothrida, 
Davainea cesticillus, and Hymenolepsis carioca. 

A general examination was made of the living birds at the 
poultry farm and it was discovered that symptoms of cestode dis- 
ease were manifested by the great majority of the chickens, al- 
though the infection was apparently not heavy except in a small 
percentage of the flock. 

In making examinations upon dead birds infested with Dava- 
inea ecJiinohothrida it was found that large nodules were formed 
in the intestinal wall which is a characteristic pathologic effect 
of this particular spiny-suckered form. Davainea cesticillus seems 
to be almost universally present as there was hardly an infested 
bird examined in Nebraska or Illinois that did not harbor some of 
this species. 

The following table shows the amount of infection and the 
number of worms occurring in each bird examined, both in Ne- 
braska and Illinois : 

No. of No. of No. of No. of No. of CI). 

DATE LOCALITY Age of D. cesti- D. tetra- D. echino- Hymeno. infundibu- 

iiost cillus gona bothrida carioca liformis 

July 25, 1912 Hardy, Neb. 4 mo. 5 

" 29 '■' 4 mo. 2 8 

August 2 " 5 mo. 3 

" 7 " 5 mo. 3 15 20 2 

" 8 " 5 mo. 10 25 10 

" 9 " 5 mo. 10 35 

" 10 " 5 mo. 5 15 5 2 

" 11 " 5 mo 7 10 3 

" 12 " 5 mo. 10 10 30 3 

" 15 " 5 mo. 5 4 1 

" 20 " Adult 

" 20 " 5 mo. 3 15 3 1 

" 21 " 5 mo. 15 10 

" 21 " 5 mo. 3 2 2 

<' 22 '^ 5 mo. 3 8 3 



CESTODE INFECTION IN CHICKENS 



223 













No. of 


No. of 


No. of 


No. of 


No. of Ch. 


DATE 




LOCALITY 


Age of 


0. CBSt- 


D. tetra- 


D. echino- 


Hymeno. 


infundlbu- 








1 


Kost 


cillus 


gona 


bothrlda 


carloca 


liformis 


{ I 


23 


(I 


5 


mo. 


3 


3 




2 


2 


I e 


25 


it 


5 


mo. 


5 


10 




10 




it 


27 


it 


5 


mo 


6 


4 






5 


i< 


29 


it 


Adult 












September 


2 


it 


Adult 












( c 


4 


i t 


6 


mo. 


5 


20 




10 




( I 


6 


1 1 


6 


mo. 


15 


10 






6 


( ( 


7 


Hardy 


6 


mo. 


10 


14 






5 


t c 


8 


i'l 


6 


mo. 


4 


10 






2 


1 1 


9 


1 1 


6 


mo. 


10 


10 




5 




January 2, 1913 


1 1 


Adult 


3 








5 


March 


23 


1 1 


Adult 












e ( 


25 


1 1 


Adult 












I ( 


30 


i t 


Adult 












April 


27 


i I 


Adult 


10 










June 


17 


1 1 


Adult 












1 1 


24 


t i 


Adult 












t c 

t e 


21 
23 


Urbana 

i I 


2 

2 


yi-. 












C I 


28 


I i 


2 


y. 












July 7, 17, 20 24 


Hardy 


4 


mo. 


infection, but recor 


ds inci 


omplete. 


August 


10 


" 


4 


mo. 


5 


10 






15 


( ( 


11 


i 1 


4 


mo. 


3 










( ( 


15 


1 1 


4 


mo. 










3 


( ( 


16 


1 1 


5 


mo. 


15 


30 




20 


10 


( < 


17 


it 


5 


mo. 


25 


30 




5 


8 


( I 


19 


1 1 


5 


mo. 


6 


15 






5 


Cl 


20 


1 1 


5 


mo. 


6 


6 








( c 


26 


i t 


5 


mo. 




15 


2 






1 1 


26 


1 1 


5 


mo. 


20 


25 


8 




10 


( ( 


27 


1 1 


5 


mo. 


1 


5 


4 






i < 


28 


1 1 


5 


mo. 


2 


10 




10 


5 


i I 


28 


( I 


5 


mo. 


10 


10 






6 


1 1 


30 


Hardy 


5 


mo. 


8 


18 






3 


September 


2 


< i. 


Adult 


3 


12 






4 


<< 


4 


1 1 


5 


mo. 


20 


20 








< ( 


6 


I ( 


7 


wks. 


17 








8 


11 


10 


1 1 


5 


mo. 


8 






10 


5 


tc 


10 


I <, 


5 


mo. 


15 


25 






4 


(I 


11 


< t 


5 


mo. 


10 


15 






4 


1 1 


12 


1 1 


5 


mo. 


25 


35 






15 


t ( 


13 


1 1 


5 


mo. 


8 


10 


4 




8 


( ( 


15 


1 1 


6 


mo. 


10 


10 






5 


< < 


16 


1 1 


6 


mo. 


3 


30 








( ( 


17 


i i 


6 


mo. 


20 


10 








1 1 


20 


I ( 


8 


mo. 


35 


6 






10 


December 


2 


Urbana 


4 


mo. 


20 




30 






( i 


5 


C I 


4 


mo. 






3 






c t 


6 


( I 


Adult 


5 






5 




( I 


9 


i I 


6 


mo. 


6 






6 




( I 


24 


Knoxville, 111 Adult 


17 


00 


00 


00 


1 


t i 


26 


Hardy 


Adult 


1 


11 






3 


January 1, 1914 


1 1 


Adult 


3 


2 






5 



224 JOHN E. GUTBERLET 



Symptoms and Effects of Tapeworm Infection. A great 
deal has been written on the symptoms of this disease by various 
authors, but in every case they were unable to reach any definite 
conclusions on the subject. In my own study, which was exten- 
sive, I reached the following definite conclusions : The symptoms, 
while not really individual, vary to some extent with the different 
birds, with the age of the birds, and with the degree of infection. 
Some birds are affected by the disease much more than others and 
show symptoms and effects much more readily. Some birds that 
show no symptoms and appear in good health are heavily infested 
with the worms, while others showing severe effects and manifesting 
all the symptoms are not nearly as heavily infested. The age of the 
host is a factor of much importance for indicating the presence of 
an infection with the species I studied. Young, growing birds are 
affected much more than adults and show the symptoms more dis- 
tinctly. Even a comparatively slight infection can be detected in 
a young bird a few weeks of age, while a heavy infection is very 
marked. Most adults manifest no external symptoms as far as 
appearance is concerned unless they are heavily infested. The de- 
gree of infection is another factor which is of importance in 
making a diagnosis for cestodes. Birds that harbor only a few 
worms show conditions which are quite different from those that 
possess a large number. Therefore the symptoms are rather var- 
iable. 

Stiles (1896: 13) mentions some general principles for diag- 
nosis, and Zurn (1882: 17) gives more fully some of the symptoms 
that may be taken as indications of the disease in the birds. 

In general, one may say that a light infection can hardly be 
noticed and is apparently in no way harmful to the fowl. In 
cases suffering from a moderate to a heavy infection the conditions 
were found to be quite different. In the first place, birds that are 
moderately infested are apparently always hungry, having in- 
deed ravenous appetites and seeming never to be able to get enough 
to eat. Secondly, they manifest a great desire for water, increas- 
ing in cases where the infection is heavy. Moreover, infected birds 
are greedy and it seems as if their hunger had caused them to lose 
control of themselves whenever there is a chance to obtain any food. 
Such birds are also restless, always moving about as if searching 
for something. This in part probably accounts for the fact that 
the fowls are poor in flesh and more or less in an emaciated con- 



CESTODE INFECTION IN CHICKENS 225 

dition. They are never at ease on account of their restless atti- 
tude which is apparently due to nervousness. Normal exercise 
alone does not depress the condition of the bird, but rather the 
constant restlessness and uneasiness which is manifested by those 
that are infested. 

The heavily infested chickens become emaciated and lose their 
color, the feathers become ruffled, and the plumage is not glossy as 
in the fowls that are free from the disease. Growing birds that 
were heavily infested, were found usually to be slender and 
quite poor in flesh, the head very thin and the comb pale. In 
cases of heavy infection the growing birds isolate themselves to 
some extent and often allow the wings to droop and hang at the 
sides. The sick birds, even though they isolate themselves, still 
manifest a great desire for food and water. 

A slight infection is hardly to be detected in the droppings, 
but when it is heavy there is developed an irritation or inflamma- 
tion of the intestinal epithelium, a kind of catarrh which results in 
a diarrhea, varying with the degree of infection. This irritation 
of the intestinal epithelium by the worms causes an abundant flow 
of mucus into the intestine. The mucous secretion is at first a 
clear, transparent semi-liquid, and sometimes slightly whitish. 
Worms which are slightly transparent are difficult to see, as they 
are imbedded in the mucus. Later the mucus takes on a brownish 
color which is due in part to slight hemorrhages of the epithelium 
caused by the irritation of the worms. This color of the mucus is 
retained until it is passed out with the feces so that the droppings 
of an infested bird have always a characteristic yellowish-brown 
color. This factor of coloration in the droppings is one that can 
nearly always be depended upon as a criterion of infection. 

When the infection is heavy a gas is formed in the intestine 
which is noticeable in the droppings in the form of bubbles. These 
bubbles are present when the feces are first passed and remain in 
the semi-liquid droppings for some time. This is very character- 
istic in cases of heavy infection but is not noticeable at other times 
except in cases of extreme diarrhea, and then. the gaseous forma- 
tion is comparatively slight. In a flock that is heavily infested 
nearly every dropping detected about roosting or resting places 
shows the characteristic yellowish-brown color with a large number 
of small gas bubbles enclosed. The infested birds pass droppings 
often, though in small quantities. 



226 JOHN E. GUTBERLET 



Segments of the worms can usually be found when there is 
a moderately heavy infection, and eggs can nearly always be dem- 
onstrated by the aid of a microscope, but the latter method is not 
practical under all circumstances. When the above methods fail 
to show any signs of infection and an absolute diagnosis is desired 
it may be well to take a few of the birds that show some of the symp- 
toms, kill them and make an examination of the contents of the in- 
testine between the gizzard and caecum. Any infection which 
cannot be detected by the above methods is so slight that it is not 
harmful to the birds in any way, or is so recent that the cestodes 
are too small to be seen. 

The best criteria for diagnosis are the emaciated condition of 
the birds, the great desire for food and water, and the marked diar- 
rhea with the characteristic yellowish-brown color of the droppings ; 
furthermore in cases of lieavy infection segments of worms can 
usually be detected, though there is some degree of uncertainty in 
making gross examinations for the proglottids in the feces. The 
excretions from the kidneys are white in color and at times have 
somewhat the appearance of the tapeworm proglottides. This may 
at times be misleading to one who is inexperienced with this method 
of examination. The excretion from the kidneys can be readily 
distinguished from proglottids by placing the droppings in water 
and breaking up the mass. Proglottids have a definite shape and 
are firm, while the excretions break up into fine granules, or shreds 
which are easily disintegrated by shaking. 

Some of the above symptoms for cestode infection are iden- 
tical with those for nematodes : the emaciated, unthrifty condition, 
the ruffled, dull appearance of the feathers, and the more or less 
restless attitude of the bird. The feces, however, look quite differ- 
ent and often blood is passed with the droppings in cases of 
nematode infection. The nematodes produce hemorrhages in the 
intestine by boring into the epithelium. 

Tapeworm infection is harmful according to the degree of in- 
fection. A slight infection does practically no harm to the bird, 
but when there is a heavy infection the condition is more serious. 
The intestinal inflammation or catarrh is quite a serious matter 
and in many cases may prove fatal. It brings on a more or less 
anaemic condition and the bird 's general health is run down. Such 
a condition is suitable for the coming in of other diseases, since 
the fowl is unable to ward them off because of its weakened state 



CESTODE INFECTION IN CHICKENS 227 

of health. Through these means the tapeworms are most harmful, 
as their effect works more or less indirectly with other diseases. 

I have found instances where the worms were so numerous 
that they would form such a large compact mass in the intestine 
as to interfere with passage. These masses imbedded in a great 
quantity of mucus become lodged at the junction of the small and 
large intestines with the caeca. 

One species, Davainea ecJiinohothrida, produces nodules or 
ulcers in the intestinal wall which are often mistaken for other 
diseases. This has a more serious effect upon the chickens than 
some of the other species as it has more of a direct pathological 
effect. 

Chickens infested with any of the species of common tape- 
worms devoured great quantities of food, but upon examination the 
intestines were usually found empty. It seems as if the food 
material after reaching the intestine rushes through rapidly on 
account of the large amount of mucus and the marked diarrhea. 
This does not allow the bird to obtain as much nourishment as it 
would otherwise. The cestodes of course absorb their nourishment 
from the chyme in the intestine. Furthermore, the excretions from 
the worms may also have some effect upon the general health of 
the bird, as some are without doubt resorbed into the system from 
the intestine. 

More practical proof must be obtained by experimental study 
on the various effects and symptoms of infection in chickens before 
much can be definitely said on the subject. As yet there is but 
little known in regard to definite symptoms and effects except in a 
general way. 

Methods of Control. The subject of the control and treat- 
ment of tapeworm disease in chickens has not been studied exten- 
sively. There is need of more experimental data before much can 
be said concerning it. Several remedies, however, have been tried 
with some degree of success, although they do not seem practical 
when large numbers of birds are to be treated. 

A practice general among poultfy raisers is to isolate a sick 
bird and leave it to cure itself, or to kill it. Most poultry men do 
not take the trouble to treat a sick bird nor do they even try to 
find out the cause of its ailment, but simply say that it has "gone 
light." Such an expression covers a multitude of diseases pre- 
valent among poultry. Birds that are heavily infested with worms 



228 JOHN E. GUTBERLET 



isolate themselves and become emaciated. They are also said to 
have "gone light." 

As the first prerequisite for carrying on any sort of treat- 
ment for worm diseases, the infected birds must be isolated from 
the rest of the flock so that the latter can be kept free from con- 
tamination. The droppings from the sick birds must be cared 
for or destroyed in some way so that the embryos of the worms are 
killed and insects prevented from feeding on them. In general 
for any flock, preventive measures should be taken against infection 
of all kinds by keeping the surroundings clean and sanitary; all 
droppings around roosts should be collected often or subjected to 
such treatment as will render them harmless or inaccessible to in- 
sects. Wherever an infection is present, even if only slight, such 
preventive measures should be taken to eliminate all possibility of 
its further increase. One of the best is to collect the droppings 
about the coop daily and place them into vats or cans that are in- 
accessible to insects or worms; they are then treated with lime 
or some substance which destroys the embryos. Lime or ashes 
should be scattered over the droppings around the roosts and the 
resting places of the birds. This destroys the embryos and keeps 
insects from feeding upon the droppings. Furthermore, if the 
droppings are covered with lime and collected often it will prevent 
insects from breeding in them. House-flies especially, lay eggs in 
chicken manure if the droppings are not treated with lime. 

Other features in the habitat of the birds should be kept 
sanitary ; such are the feeding places and drinking vessels. Water- 
ing troughs should be so placed that the birds cannot get their feet 
into them, as they may carry in eggs or embryos of other para- 
sitic worms (nematodes) which will reach the birds again through 
the water if the latter is allowed to stand in a filthy condition. 

The location of poultry yards should be changed from time to 
time if possible, because if the same grounds are used from year 
to year some of the insects that may be the intermediate hosts of 
the tapeworms may become numerous and thus increase the possi- 
bility of infection. Embryos of parasites or germs of certain dis- 
eases remain on the premises from year to year, and if the yards are 
changed, more healthful conditions are produced for the birds. 

In addition to destroying the eggs and embryos of parasites 
in the droppings, it is fully as important to destroy the adult in- 
sects and their breeding places. The life history of only one spe- 



CESTODE INFECTION IN CHICKENS 229 

cies of tapeworm has been worked out in the United States, as is 
discussed elsewhere in this paper. This species is known to have 
its intermediate stage in the house-fly. House-flies breed commonly 
in bird or horse manure, or any decaying vegetable matter. The 
destruction of all such breeding places is a difficult matter and 
little can be done along that line or with the destruction of adult 
flies. However, fly traps* can be placed over the windows of the 
chicken coop and many flies caught and killed. 

According to Stiles (1896:18), the principal remedies that 
have been used for the removal of tapeworms from poultry are 
such drugs as extract of male fern, turpentine, powdered kamala, 
areca nut, pomegranate root bark, pumpkin seeds, and sulphate of 
copper. These have been experimented with to a certain extent 
and have been found to be satisfactory in some instances. 

The experiments with these remedies have been worked out 
on individual birds. Each bird must be treated individually. 
"While such methods of treatment are thorough, they are not prac- 
tical for a poultry raiser who has an infection in a flock of several 
hundred birds. It would require handling each bird separately 
two or three times, and demand a considerable amount of time ; too 
much to be practicable on account of the expense involved. 

I tried experiments on a number of birds to see whether a 
more practical method could be found. It had been observed 
previously that hogs infected with worms could be freed from them 
by feeding the ashes from corncobs. The ashes contain a large 
amount of sodium and potassium carbonate. Lye is made from ashes 
and of course contains similar substances, together with sodium hy- 
droxide. 

The following experiment worked very successfully: Fifteen 
birds which showed symptoms of tapeworm infection were placed 
in a cage which was insect-proof and were given the following 
treatment; A gallon of a mixture of wheat and oats, to which 
was added a small tablespoonful of concentrated lye, was cooked 
slowly for about two hours and allowed to cool. The birds were 
fasted for about fifteen hours and were then given as much of the 
mixture as they would eat, with plenty of water. Twelve hours 
later one of the birds was killed and an examination of the small 
intestine was made. It was found that nearly all of the worms in 



•^Such as described by F. C. Bishopp, Farmers ' Bulletin No. 540, 1913. 



230 JOHN E. GUTBEBLET 



the intestine were loose, the scolices being detached from the wall, 
and were also apparently dead. The rest of the birds were given 
a second dose twenty-four hours after the first. Many worms had 
passed with the droppings in from twenty-four to twenty-six hours 
after the first feeding. Most of the worms in these droppings 
were dead, but in all probability the embryos were still alive in the 
mature proglottids. Twelve hours after the second dose was given 
another bird was killed and it was found that only a few worms were 
left and all of these were detached and dead. The intestine was 
filled with a peculiar gray colored, slimy substance composed mainly 
of mucus. Many entire worms and fragments were passed with 
the droppings during the period of the feeding. The lye acted to 
some extent as a purgative. 

The birds were given normal diet again, and in a few days 
they showed no symptoms of infection. Eight days after the sec- 
ond dose two more birds were killed and examinations made. One 
possessed a small fragment of a tapeworm and the other was en- 
tirely free. 

The effects of such treatment upon the flock as a whole were 
shown later. While I was carrying on other investigations with 
chicken cestodes my father noticed that the birds were very heav- 
ily infested with worms. In an endeavor to free the birds of the 
worms and to improve their general condition he fed them a mix- 
ture of cooked grain and lye on July 15, unknown to me. As a 
result the entire flock of nearly four hundred birds was practically 
freed from the worms by a single application of the remedy. The 
cestodes were so thoroughly removed that there were not enough left 
to allow me to go on with my investigations and my observations on 
the worms were not taken up again until August 10, when the birds 
had become infested again and the parasites had grown to such size 
as to enable the continuance of my work. 

This remedy is a very simple one and is practical. It has 
been known to many poultry raisers for some time, but they have 
neglected to use it, mainly on account of the fact that heretofore 
no definite evidence has ever been presented concerning its actual 
working possibilities. It may not, and in all probability will not, 
remove all the worms, but it does remove most of them so that they 
are not serious and can be controlled in the flock as a whole. 

In a large flock the birds can be housed for the length of 
time required for the fast, then fed on the cooked grain and kept 



CESTODE INFECTION IN CHICKENS 231 

in the house until after .the effects of the second dose have passed 
off. During the time that they are confined the droppings should 
be collected often and lots of lime used about the coop and over 
the droppings to keep away the insects. In a flock the treatment 
would have to be repeated from time to time whenever the birds 
became infected again. Further experimental evidence must be ob- 
tained before much can be said in regard to details of this method 
of treatment, especially as to the amount of the alkali to be used. 
A large amount would be harmful to the intestinal mucosa, while a 
small amount would have little if any effect upon the parasites. 

Feeding Experiments for Infection. Chickens in the vicin- 
ity of Hardy, Nebraska, were heavily infested with tapeworms, and 
young birds were found to be more heavily infested than the adults. 
This led to investigations concerning the reason for the difference 
in the infestation of the adult and young birds when they were to- 
gether in the same environment and fed on the same diet. 

The summer of 1913 was very dry in the locality which was a 
factor in keeping the numerous varieties of insects down to a min- 
imum, because the drought interfered with their breeding. Upon 
observation it was found that only two kinds of insects were present 
in any abundance about the haunts of the birds. Those were the 
ground beetle Tenehrio and flies. The stable fly, Stomoxys calci- 
trans, which usually breeds in wet, decaying straw, was very scarce 
because its breeding places had dried up. The house flies were 
very abundant everywhere. 

The reason why the adults should be only slightly infested 
with parasites, while the young and growing birds harbored so many, 
was then the subject for observation. The birds were watched in 
their haunts and their habits studied. It was soon noticed that 
the young birds, when in their resting places in the shade of a tree 
or a building, were busy the whole time pursuing flies and very 
often caught their prey, while the adults paid little or no attention 
to the flies. This led to the conclusion that flies might have some- 
thing to do with the transmission of the worms to the birds. 

With a view to testing this hypothesis, experiments were car- 
ried on with the worms that were most common in the birds. 
These species were Davainea cesticillus, Davainea tetragona, and 
Choanotaenia infundihuliformis. 

Segments of these worms were teased apart so that the eggs or 
embryos were set free in a drop of water, and this was fed to flies 



232 JOHN E. GUTBERLET 



of the species: Musca domestica, Stomoxys calcitrans, and CalU- 
phora vomitaria. 

Only a few Calliphora could be obtained and these did not 
live long under experimental conditions. This species of fly does 
not frequent places where it would be likely to become the inter- 
mediate host of any of the chicken cestodes, as it always remains in 
cool, damp, and usually dark places, unless it can find carrion. 
However, on cool, dark, damp days it does appear in chicken yards, 
but its occurrence there is 'not frequent. Some Stomoxys were used, 
but in no case did they live long in captivity. 

Musca domestica lived much longer than either of the others, 
even though it was difficult to keep them alive for a long period. 
After a great deal of experimentation it was found that they could 
be kept alive in a cage for twelve or thirteen days, and in one ex- 
treme case some were kept alive for twenty-one days. The flies in 
captivity were fed on blood, liver and spleen. These were found to 
be the best foods. 

The oldest proglottids on the worm were usually taken for 
feeding to flies, and also some of the free segments in the intestine 
were used. The use of the oldest proglottids proved to be an error 
in the case of Choanotaenia infundihuliformis, because it was found 
later that in this species the oldest segments separate from the 
worm before they are entirely mature, but proglottids that have been 
free in the intestine for some time may be mature. The use of 
proglottids that were not entirely mature for feeding flies was an 
error in my experiments which may account for so few infections. 

Davainea cesticillus. In a series of experiments 107 flies of 
the species Musca domestica were fed on the eggs from proglottids 
of Davainea cesticillus. Some were killed and preserved each day 
from the beginning of the experiment until the tenth day, when the 
remaining flies died, except in one case four were kept alive for 
twenty-one days. These were all sectioned with the exception of 
five, which were dissected. No stages of the cestodes were found in 
any of the flies when examined. 

During the experiment microscopic examinations were made of 
a great number of the droppings of the flies and no eggs or embryos 
of the worms could be found in any case. It is certain that the 
flies got some of the eggs because they were numerous in the mater- 
ial that was fed to them. The flies would lap up all the water in 
which the eggs floated and would then suck on the fragments of 



CESTODE INFECTION IN CHICKENS 233 

proglottids. In several instances when the flies were hungry it 
was observed that they would take small fragments of the proglot- 
tids between the labella of the labium and actually devour them. 
Since the eggs are microscopic in size it is practically certain that 
the flies got some of them. 

Several Calliphora were fed on eggs from this species, but 
these flies lived for only two or three days. 

Proglottids of this tapeworm were fed to a number of beetles 
of the species Tenehrio melitor. The beetles ate the segments 
readily. Some were killed at the end of one week, others at two 
weeks, and the rest at three weeks. These beetles were sectioned, 
but showed no developmental stage of cestodes. 

Davainea tetragona. In experiments on this species 59 flies 
in all were used. Some of these were killed and preserved after 
from two to twelve days. The proglottids were broken up and 
the eggs set free in a drop of water. The flies lapped up the water 
with the eggs and afterwards sucked all of the moisture from the 
fragments of the proglottids. Therefore, it is very probable that 
the flies got some of the eggs. Microscopic examinations of the 
droppings of the flies showed no signs of eggs. 

Material would pass through the flies in a few hours as was 
demonstrated by feeding them on blood. When the flies gorged 
themselves with blood they passed red droppings in from eight to 
ten or twelve hours. This indicated the length of time that it took 
material to pass through the alimentary canal. In this way the 
approximate time to make fecal examinations for the eggs was de- 
termined. However, examinations were made of the droppings 
after five or six hours as well as later and at regular intervals of 
two or three hours. 

The flies were fed on eggs once or twice each day for three days. 
When they were fed once a day that was done in the morning, and 
when fed twice they were given one dose in the morning and the 
other at noon. On three occasions some flies were fed in the even- 
ing and fecal examinations were made the next morning and con- 
tinued at intervals of two or three hours. 

The flies were all sectioned and examined, but showed no stages 
of the cestodes in any instance. 

Some Calliphora were fed upon the eggs of this species, but 
they did not live more than two or three days. Some beetles, Ten- 
ebrio, were fed on proglottids, but upon examination they showed 
nothing. 



234 JOHN E. GUTBERLET 



Choanotaenia infundibulipormis. Eggs of this species were 
fed to 88 flies of the species Musca domestica. Besides these some 
Stomoxys calcitrans were also fed, but these did not live long in 
captivity. The individuals of Musca domestica used in these ex- 
periments lived from two to seventeen days. Two flies lived for 
twelve days and four for seventeen days. The proglottids were 
broken up and fed to the flies in the same manner as in the other 
species mentioned. All of these flies were sectioned and examined. 
One fly preserved at the end of twelve days showed five cysticerci. 
These cysticerci agree very closely with the structure of the adult 
of this species, and the hooks are identical. This cysticercus is de- 
scribed in detail in another paper. 

Grassi and Rovelli (1892: 33) found cysticerci in flies which 
they compared with this species. They found that there was a close 
agreement in structure between the cysticerci they discovered and 
the adult of Choanotaenia infundihuliformis. They therefore in- 
ferred that the larva they had was the intermediate stage of this 
species, but did not demonstrate experimentally its connection with 
the adult tapeworm. 

During the process of my experiments I had hoped to be able 
to feed some chicks on flies that had been previously fed on tape- 
worm eggs, but as it was so difficult to keep the flies alive under ex- 
perimental conditions such an experiment could not be carried out. 
However, another feeding experiment was tried with the following 
results : Six chicks were taken from the nest as soon as they were 
hatched and placed in a cage where they could get no insects and 
great care was taken during feeding so that no flies could enter. 
Flies (Musca domestica) were caught around the chicken roosts and 
fed to three of the chicks. The other three birds were used as a 
control and were given no flies. Fifty flies were fed to each of 
the three chicks. Three weeks after feeding, the chicks were killed 
and examined with the result that two were found to be infested 
with Choanotaenia infundihidiformis. One bird possessed six 
worms. These were of the same length, being 35 mm, long, and each 
one contained 103 proglottids. The other bird had one worm of 
the same species, but it was a little longer, 43 mm. and having 118 
proglottids. This bird was fed on the flies three days before the 
one sheltering the six worms. The three birds which were used as 
a check on the experiments contained no worms when killed and ex- 
amined. 



CESTODE INFECTION IN CHICKENS 235 

These six birds were kept together in a cage and were fed on 
corn meal and bread crumbs. The three birds that were fed flies 
were caught and the insects were given to them from the hand. 

A number of stable flies (Stomoxys calcitrans) were used in 
the experiments with this species of worm, but they would not live 
under experimental conditions for any length of time. They would 
usually die within 24 to 36 hours, except in one case when six lived 
for five days. They were sectioned, but nothing could be found. 

On numerous occasions I have observed maggots in the drop- 
pings beneath the chicken roosts. Now, since house-flies are in the 
habit of breeding in such places, it seemed possible that infection 
might take place in the maggot stage of the flies. Experiments 
were then tried with the maggots of Musca domestica and Stomoxys 
calcitrans. Thirty Musca domestica maggots were fed on segments 
of three species of cestodes, Davainea cesticillus, Davainea tetra- 
gona, and Choanotaenia infundihidiformis. The maggots devel- 
oped puparia in a day or two. Some were sectioned in the pupa 
stage. The rest developed into adults and were sectioned, a few 
were dissected, but only negative results were obtained. Fifty 
maggots of Stomoxys calcitrans were fed on proglottids of the same 
three species of tapeworms. The maggots went into the pupal stage 
within two or three days. Some were sectioned in the pupal stage. 
Most of them developed into adults and were sectioned while a few 
were dissected. No positive results were obtained from either pupal 
or adult stages. 

From the foregoing it seems probable that flies are not the 
intermediate hosts for Davainea cesticillus and Davainea tetragona, 
as the experiments that I have carried on with them are extensive 
enough to appear conclusive. However, the small number of vari- 
eties of insects present in the locality seems to throw the burden 
upon the flies, since they were so abundant and observations show 
that they are taken and eaten by the chickens that are most heavily 
infested. The adult birds eat all other insects that are easy to 
catch, but since the flies are more difficult to take as prey they 
leave them alone. If the infection is direct, the adults would have 
fully as much chance as the young birds because they get food and 
water together and have the same environment. 

In the case of Choanotaenia infundihidiformis it seems to be 
clear that the house-fly is the intermediate host. Grassi and 
Eovelli hold that it is the intermediate host on a purely structural 
basis. My experiments show that it is certainly an intermediate 



236 JOHN E. GUTBERLET 



host in some cases. Furtherwore, feeding chicks on flies that were 
taken from about the chicken roosts and raising the cestodes make 
it probable that the house-flies are the intermediate hosts of this 
one species. 

The reason why more flies were not infected by feeding on 
the eggs of this species was determined to be peculiar conditions in 
the maturing of the proglottid. At the time when the experiments 
were being carried on it was not known that the oldest proglottids 
separated from the worm before they are entirely mature. In the 
experiments the oldest proglottids on the worm were usually taken 
for feeding, though in some cases the free segments in the intestine 
were used. Since the flies were fed on eggs that were not entire- 
ly mature the embryos were digested. The free proglottids remain 
in the intestine of the bird for some time and in all probability 
mature there. Some such free proglottids were examined and found 
to contain mature embryos. 

SUMMARY 

1. The results of these experiments show that the intermediate 
(cysticercoid) stage of Clioanotaenia infundibuliformis occurs in the 
common house-fly Musca domestica. The results were obtained by 
feeding flies on eggs of the tapeworm and raising cysticercoids in 
a fly ; also by feeding chicks on flies and raising the worms in the 
birds. By morphological comparison of the cysticercoid and adult 
they are shown to be identical. Results from experiments by feed- 
ing flies on eggs from Davainea cesticillus and Davainea tetragona 
were negative. 

2. The habits of the birds are important factors to be con- 
sidered in experimental work for life history studies. Certain in- 
sects are found in great numbers around chicken houses and 
yards and are readily eaten by the birds. Flies are known to con- 
tain the larval stage of one species of cestode, and some other 
species of insects are to be considered as probable intermediate 
hosts for other species of cestodes. 

3. The symptoms and effects of the infection from tapeworms 
vary with individual birds, age of birds, and the degree of infec- 
tion. Birds infested with worms display an emaciared, unthrifty 
condition, an unnatural desire for food and water, and a marked 
diarrhea with- droppings of a characteristic yellowish -brown color. 

4. The control of tapeworm disease in chickens is in an unset- 
tled condition. Little can be done until more is known concerning 
life histories of worms. Preventive measures are urged rather 



CESTODE INFECTION IN CHICKENS 237 

than curative measures. Droppings should be cared for and treated 
with appropriate substances in order to prevent insects from feed- 
ing on them or developing in them. Experiments by giving lye 
with food to infested chickens showed satisfactory results in re- 
moving tapeworms. 

5. The flocks of chickens that were studied showed at times a 
very heavy infection and nearly every bird examined harbored one 
or more species of worms. Five species were found in the chickens 
at Hardy, Nebraska, and three in the birds at the poultry farm at 
the University of Illinois. The species found in Nebraska are 
Davainea cesticillus (Molin), Davainea tetragona (Molin), Davainea 
echinohothrida (Megnin), Hymenolepis carioca (Magalhaes), and 
CJioanotaenia infundihuliformis (Goeze). At the poultry farm of 
the University the species Davainea cesticillus (Molin), Davainea 
echinohothrida (Megnin) and Hymenolepis carioca (Magalhaes) 
were found. 

6. A full description of the structure of these parasites has 
been published in the Transactions of The American Microscopical 
Society, Vol. 35, p. 23-44, PL 5-8. 



BIBLIOGRAPHY 

Grassi, B. B. and Eovelli, G. 1889. Embryologisehe Forschungen an Ces- 
toden. Centralbl. f. Bald, und Parasitenk, 5:370-377, 401-410. 
1892. Ricerclie embriologiche sui Cestodi. Atti Accad. Gioenia di Sci. 
Nat. in Catania, 4:1-108. 
PlANA, G. P. 1882. Di una nuova specie di Tenia del gallo domestico (Taenia 
bothrioplitis) e di.un nuova cisticerco delle lumachelle terrestri (Cyati- 
cercus bothrioplitis). Mem. Accad. Sci. Inst. Bologna, 2:387-394. 
Eansom, B. H. 1900. A new Avian Cestode— Metroliasthes lucida. Trans. 
Amer. Micr. Soc, 21:213-226. 

1902. On Hymenolepis carioca (Magalhaes) and H. megalops (Nitzsch) 
with Remarks on the Classification of the Group. Trans. Amer. Micr. 
Soc, 23: 151-172. 
1904. The Tapeworms of American Chickens and Turkeys. Bur. An. Ind. 

Ann. Bpt., 21: 268-285. 

1909. The Taenoid Gestodes of North American Birds. Bull. U. S. Nat. 

Mus., 69 : 1-141. 

ROSSETER, T. B. 1891. Sur un Cysticercoide des Ostracodes, capable de se de- 

velopper dans I'intestin du Canard. Bull. Soc. Zool, France, 16: 224-229. 

1892. On a New Cysticercus and a New Tapeworm. Journ. Queckett 

Micr. Club, 4: 361-366.. 
1897, On Experimental Infection of Ducks with Cysticercus coronula 
Mrazek (Rosseter), Cysticercus gracilis (von Linstow), Cysticercus tenui- 
rostris (Hamann). Journ. Queclett Micr. Club, 6: 397-405. 
Schmidt, J. E. 1894. Die Entwicklungsgeschichte und der anatomische Bau 

der Taenia anatiua (Krabbe). Arch. f. Naturg., 1894, 1: 65-112. 
Stiles, C. W. 1896. Report upon the Present Knowledge of the Tapeworms 

of Poultry. Bur. An. Ind. Bull. No. 12; 78 pp. 
Tower, W. L. 1900. The Nervous System of the Cestode Monezia Expansa. 

Zool. Jahrb., 13: 359-384. 
ZtJRN, F. A. 1882. Die Krankheiten des Hausgefliigels. 237 pp., 76 figs, 
Weimar. 



VITA 

John Earl Gutberlet was born in Nebraska in March, 1887. 
He received his preparatory training in the high school at Hardy, 
Nebraska, and at Bethany Academy, Lindsborg, Kansas. He 
entered Bethany College, Lindsborg, Kansas, in 1905 and received 
the A. B. degree from that institution in 1909. During the year 
1909-10 he was a graduate student and an assistant in the 
department of Zoology at the University of Colorado. He 
attended the summer session of the University of Colorado 
Biological Station in 1910. In the fall of 1910 he went to the 
University of Illinois where he accepted a position as assistant 
in the department of Zoology which he held until 1913. He 
received the A. M. degree from the University of Illinois in 1911. 
During the summer of 1911 he was engaged in study at the Marine 
Biological Station, La Jolla, California. He was elected to mem- 
bership in the Illinois Chapter of Sigma Xi in 1912. He attended 
the summer session of the University of Illinois in 1913. During 
the year 1913-14 he held a fellowship in Zoology at the Univer- 
sity of Illinois where he completed his work for the degree of 
Doctor of Philosophy in .June, 1914. 



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